Temperature to remain high as dry days set to continue in Tamil Nadu

The western end of monsoon axis runs along the foothills of Himalayas and the eastern end passes through North East India. This will result in heavy spells in the entire North East India with extreme rainfall of over 250 mm expected in Meghalaya. In the last 24 hrs. RKM Cherrapunji and Nongstain in Meghalaya have registered 259 and 240 mm rainfall respectively. The Dooars in West Bengal has also been getting heavy rains with Hasimara recording 216 mm rainfall. Floods in Assam can worsen if the rains prolong for a long time.

A trough, which persists from east Bihar to south Odisha, in conjunction with the Upper Air Circulation (UAC) will continue to give rains to West Bengal, Bihar, Jharkhand, Odisha and north Andhra Pradesh. With the monsoon axis shifting to North East, rest of the country will mostly see subdued rainfall. Temperature in Tamil Nadu will continue to remain above normal with less chance of rains.
Chennai – Hot days to continue with temperature peaking around 37C.No chance of rains.

Coimbatore – Hot day as per Coimbatore standards as temperature rise to 34C with no chance of any showers.

Madurai – A hot and blazing day on cards and mercury could test 39 C. Chances of rain remains nil.

PJ, Its nothing surprise about yesterday’s rains based on trough extension till TN from CC stayed along SWM-axis that too with MJO at close to phase 2. Previously August 4th rains also happened due to same type phenomenon from Komen’s CC (aided by properly oriented WP-typhoon’s pulling from near by Philippines). Chennai received so many times in previous years also and will happen in future too.

Same type intense rains over core-Chennai will again happen on September 3rd late night onwards.

Flash…high intensity electric VS-TS (hybrid) for Core Chennai on September 3rd night (late night):
A very high intensity electric VS-TS (hybrid) may occur at many places over core Chennai on September 3rd night (most probably from late night onwards). In most places RF will cross 50 mm within short time & with 1 or 2 places to receive RF close to 100 mm mark. This electric TS can be more intense than august 30th and close to August 4th TSs that occurred at core Chennai.

Height of confidence based on:
MJO’s close proximity at phase 1or 2 with ER at phase 2(both by GFS & ECMWF) with perfect orientation of trough line extension from CC around Orissa/WB/Jharkhand till TN with abundant moisture available at 700 hpa level on September 3rd.

I request Kea to make the above comment as featured (any time) in order to avoid confusion about the forecast if it turns reality on September 3rd. Our friends are allowed to daunt me if the above forecast turns -ve 🙂

Folks, as most of us feeling sad when it doesn’t rain before evening, few comments also talked low steering wind’s etc, but we saw fairly decent spell late night. That’s the power of nature. Chennai rocks.

Omg…yesterday storm was very thrilling and massive… After that small storms, in no time that vellore storms converged and intensified… Most of them think that is for south chennai.. But pj came and told to check ppv. It was amazing to check storm direction towards radar..pj was confident that storm for central and north chennai where all expected for south chennai including me.. Finally storm went for pj route as per ppv..it was very interesting yesterday in storm movement…
Anna nagar got some 55 mm ( 40 mm in 30 minutes)
Unfortunately storm missed south chennai.. My area recorded only 12 mm

India is finally ready with its own indigenous model to predict long range and seasonal rainfall. In the next six months, the Indian Institute of Tropical Meteorology (IITM), Pune, is all set to operationalise a dynamic numerical climate model it has developed to forecast extended-range rainfall for 15-20 days, after results from the experimental stage were found to be reliable.
“For the first time, we have indigenously developed a prediction system that was not available in India. The tests have been done, the performance of the experimental model was found to be good and can be operationalised. We can now forecast rain every five days for 15-20 days, especially for the agriculture sector, which is the mainstay of the economy,” M Rajeevan, director, IITM told HT.
Under the Indo-US joint collaboration, scientists at IITM, tasked with improving long-range and seasonal scale forecasts (16 days to a season), used the National Centers for Environmental Predictions-Climate Forecast System (NCEP-CFSv2) model for monsoon prediction.
“We are halfway to the monsoon mission. The model in the next phase will incorporate hydrological forecasting that will help in decisions relating to management of dam water, how much water can be released or whether the water can be used to generate hydropower,” said Suryachandra Rao, senior scientist, IITM.http://www.hindustantimes.com/mumbai/coming-soon-an-indian-model-to-predict-rainfall/article1-1385892.aspx

As I said last week, we got rain last night, unfortunate that my area got some drizzles.
Yesterday Meena got 1.7 MM, as per Metsite Nunga got 24.1 MM. As per IMD reading 29MM.

As per my forecast we got some rain from 27th to 30th so far. Henceforth whatever rainfall we get will go into September account as per IMD readings.

I am also surprised to see the news like ER Wave activity, I don’t think such an activity here, the following link not showing the same, it shows the ER induced negative olr effective above 15N latitude only.

One unique fact is our either part of city continuously enjoying rains on every Sundays from last month, so Sunday = sun Lord as per Hindu methodology, so sun = heat factor strongly persists, moreover last 2 days was a scorcher for chennai so accumulated heat paved way for ts…

exactly this might be due to heat factor, but not due to ER wave, there is no change wind anomaly in the past 2 days and mid level. also 500 HPA is from SE to NW, during ER wave the wind direction must be from NW to SE.

trough dip happens almost daily during swm.. when the land gets heated ,we can see the trough dipping south after 2.30,will get clearly marked after 5.30pm.. we cant say the winds would b from particular direction during ER wave..lot of micro& macro systems alter the winds ,amidst all tis ER wave moves

i am not saying particular direction, it is an example of it, when the trough dips how can it change wind direction totally opposite, when there is westerly winds, if trough dips either it should change to SW or NW, but the westerly will remain westerly, it may be diagonal but not in opposite direction completely.

also when i see 700 hpa level, there is not abnormal dip, it is perfectly from West to East. 500 HPA totally opposite.

The TS we got due to heat factor, not due to ER wave, there is no change wind anomaly in the past 2 days and mid level. also 500 HPA is from SE to NW, during ER wave the wind direction must be from NW to SE..

Almost nothing here. Paah looks like North Chennai areas got battered last night. With this, North Chennai would’ve bridged the gap with South. Very happy with this.. now Chennai’s average would be between 150 and 200 mm

There are no 2 vortices found in North and Southern Hemisphere, this is another reason for saying ER wave effect not available between 15N and 15S. The heat based synoptic conditions was involved in early morning rain.

1. I have enclosed the past vortices of October 2002, that time we had ER wave effect, that is first pic.

2. The second of today early morning, does not show any vortex.

3. The third one of today’s tropical and subtropical interactions map, which shows that there is no interaction between 30N latitude and below than that over India, the same has been shown with orange line in West Pacific, since ER wave impacting those region with suppressed wave.

4. The fourth image shows the latest status of ER wave shows cold and warm front over that region.

5. The fifth image show the vortex in WP both in North and South hemisphere.

when 15N to 15S are not having any distraction, how can you say it as ER wave influence, it is simple as that.

Only nunga has got 29MM, other places in NTN has not got anything.
Nothing in South AP also. If you see above 15N, Machilipatnam, Kakinada has got heavy rainfall last night, Cuddapah, Kurnool and Tirupathi got less than 2 MM, other areas completely dry,.

The below comment of ER related to pure ER/single ER. But the convection what we are seeing is combination of ER+KW (majorly) + MJO (minor). So it’s very difficult to identify the pure ER feature in the convection near SL (even counter weaker convection in S.hemisphere can be found) by any parameters. An equatorial wave’s OLR can be be found at more than one place at a time. http://www.imd.gov.in/section/satmet/dynamic/insat.htm

Easterly wind anomaly over Equatorial Indian Ocean, see the difference of 850 HPA wind last week and now, huge diversion towards West Indian Ocean, running to extreme west arabian sea and coming back to south india now. I have enclosed both the pictures of last week and now the wind direction changes. This is another reason for me to say no ER wave in action.

kelvin arrived few days back, increased the sst anomaly over west io, still kelvin sustaining over central io, this is stopping er, it could not enter below 15n latitude, since both kelvin and er having same intensity, the gap between 10n and 15n latitude in bay becomes hpa.

yes sir, this weak phase of MJO bringing rain to Srilanka. That is below 10N, this i have mentioned in my last week comment when i was posting forecast to Srilanka. This is following persistent Kelvin.

The CEW has become weak over Bay, since the wind direction changes over EQ IO, this is why the dry condition created between 10N and 15N over Bay.

Kelvin creating some moisture below 10N and ER creating moisture above 15N. Since NW winds have set in North and NW India, this is pushing all moistures to lower latitudes, this has created some pressure, even then the pushing is far away from us, we got some moderate rain.

Rain forecast or wave forecast? Confused as I was talking about September 3rd RF event as per featured comment (I used only earthnull school to see different levels of stream lines and Equatorial wave’s forecast. I generally don’t see any other forecasts before estimating Core Chennai’s RF probability other than these).

The main factor which is causing the HPA over bay is that, the CEW weakens due to Positive IOD. This has also bought down the ACC from Tibet to lower latitudes, this is the indication of wind pattern changed at lower levels of atmosphere.

Instead of SW to NE towards Bay, the wind now travelling from West to East due to Easterly Anomaly over Eq IO, this is brining dry winds between 10N and 15N over bay.

Yes as 850 and 250 hpa streamlines will be in almost opposite direction. In that case we can use direct 850 hpa streamlines. But why you are referring 250 hpa streamlines for discussing lower level steering pattern??

when wind direction over North India changes at lower levels, it changes or migrates the ACC over Tibet which is formed during SWM season.

this ACC will come down once the lower level wind pattern changes from West to NW over North and North West India, this pushes the upper level acc from tibet to lower latitudes and it will slowly move towards MTC in future.